IN THE BAYS ON THE SOUTH-EAST COAST OF DEVON. 455 



4 per hour in the winter, and again rising to the same original level 

 of 8 per hour in the spring, which was maintained throughout the 

 summer. The largest fish showed a similar sequence of changes for the 

 first twelve mouths, but, according to the figures, declined during the 

 last summer season to half their original frequency. 



The sequence of changes shown by the mature medium-sized plaice 

 is readily explained by the seasonal migrations of the fish, which are 

 dealt with in a later section of this report. It is there shown that the 

 plaice tend to immigrate into Start Bay from all quarters during the 

 spring and summer months, from the offshore spawning-grounds in 

 the spring, and from the other bays to the northward in summer and 

 autumn. Towards the end of the year they again leave the bay for 

 the offshore spawning-grounds. The figures illustrating the seasonal 

 changes in the abundance of the largest fish would also be explicable in 

 the same way, were it not for the unusual decline shown by the figures 

 for the last summer quarter. If reference, however, be again made to 

 Tables III. and IV., it will be seen, as previously mentioned, that 

 Station III. is represented in the records for the first four quarterly 

 seasons, but is not represented in the last, and it will be remem- 

 bered that this station is characterised by the large size of its plaice. 

 Station II. also, in which the actual abundance of marketable plaice is 

 greater than in the other stations, is represented far more conspicuously 

 during the summer season of 1901 than during that of the succeeding 

 year. If the hauls on the Skerries Bank (Station III.) be omitted from 

 the records for the first summer quarter, and if the influence of Station I. 

 on the records for the second summer quarter be reduced to the same 

 proportions as prevailed during the first, the catch per hour of the 

 difterent groups of plaice takes the following dimensions : — 



Catch per Hour. 



Season. 

 Jiily-Sept., 1901 

 Jiily-Aug., 1902 



Total. 0-7" 8-11" 12-14" 15"+ 

 18 ... 2 ... 4 ... 8 ... 4 

 28 ... 1 ... 15 ... 9 ... 3 



It will be seen that there is now no longer any material difference 

 in the evidences of abundance of the largest groups of plaice in this 

 season during the two years ; while, on the other hand, the great 

 increase in the abundance of immature medium-sized plaice becomes still 

 more obvious. As will be seen in the case of the other bays, a marked 

 increase in the numbers of this group of plaice in the summer of 1902, 

 as compared with the summer of 1901, was a general feature which 

 characterised each of the bays. 



The important question now arises : Which of these years was most 

 typical of the conditions normally prevalent in Start Bay ? Was the 

 scarcity of small plaice in 1901 normal or abnormal ? Was this marked 



